High dairy intake in adolescence may reduce risk for Type 2 diabetes

Abstract

MedWire News: Study results suggest that girls who consume large amounts of dairy in adolescence are less likely to develop Type 2 diabetes in middle age than those who consume low amounts.

Previous studies have shown that consumption of dairy products is inversely associated with presence of the metabolic syndrome and Type 2 diabetes in adults.

Advertisement

To assess whether patterns of dairy consumption in adolescence influence risk for Type 2 diabetes in later life, Frank Hu (Harvard School of Public Health, Boston, Massachusetts, USA) and colleagues assessed the incidence of Type 2 diabetes in 37,038 participants of the Nurses' Health Study II.

Women in this cohort study completed food-frequency questionnaires in 1998-2005 about their diet when they were in high school (1960-1980). They were followed-up from when they returned the questionnaire for an average of 7 years. During this time there were 550 cases of incident Type 2 diabetes.

The women were divided into quintiles of dairy product consumption in adolescence, ranging from a median of 0.5 servings of dairy products per day (one serving=1000 kcal) in the lowest quintile to 2.0 serving per day in the highest.

As reported in the American Journal of Clinical Nutrition, Hu and team found that women in the highest quintile for adolescent dairy intake had a 38% lower risk for developing Type 2 diabetes in middle age compared with women in the lowest quintile.

Advertisement

This risk reduction was still significant after adjustment for diabetes risk factors during adolescence such as total energy intake when participants were in high school and body mass index at age 18 years.

Following further adjustment for adult risk factors, such as smoking status, physical activity, and consumption of processed meat and trans fat, the association between diabetes risk and dairy product consumption persisted. However, the association was weakened after additional adjustment for adult dairy consumption.

When the researchers combined dairy product intake in adolescence and adulthood, women in the highest quintile for intake had a significant 43% decrease in risk for Type 2 diabetes compared with those in the lowest quintile.

"Some of the benefit of dairy product intake during high school may be due to the persistence of the consumption pattern during adulthood," suggest the authors.

They say: "Additional confirmation of these findings and a risk-benefit assessment including consideration of the environmental impact of dairy farming - including the use of corn-based animal feeds and the health effects of consuming dairy products from cows treated with recombinant bovine somatotropin or kept lactating for extended periods - are needed before clear public health recommendations for dairy product intakes can be made."